Device for automatic zigzag sewing



Nov. 6, 1962 SABURO SHIMADA DEVICE FOR AUTOMATIC ZIGZAG SEWING 2 Sheets-Sheet 1 Filed June 10, 1959 INVENTOR.

Nov. 6, 1962 SABURO SHlMADA DEVICE FOR AUTOMATIC ZIGZAG SEWING 2 Sheets-Sheet 2 {Jul/ll Filed June 10, 1959 INVENTOR. 5m Jimdw atent fiice 3,062,164 DEVICE FOR AUTOMATIC ZIGZAG SEWlNG Saburo Shimada, Koganei-shi, Tokyo-t0, Japan, assignor to Riccar Sewing Machine Co., Ltd., Tokyo, Japan, a

corporation of Japan Filed June 10, 1959, Ser. No. 819,432 Claims priority, application Japan Sept. 8, 1958 4 Claims. ((31. 112158) This invention relates to a device for automatic zigzag sewing which comprises a block comprising a plurality of concentric rugged cam tracks on one side for selecting any of the cam tracks by means of a selector, and changing zigzag widths according to said rugged cam tracks, whereby patterns sewn according to the selected cam tracks are obtained.

In the accompanying drawings wherein an embodiment of this invention is shown:

FIG. 1 is a plan View which shows partly in section the principal part of the present device;

FIG. 2 is a vertical cross section thereof;

FIG. 3 is a side elevational section thereof;

FIG. 4 is an enlarged perspective view of one part of the principal part of the device;

.FIG. 5 is an enlarged perspective view of a rotary profiling member; and

FIG. 6 is an enlarged perspective View of a selector plate.

Description will now be made with reference to an embodiment of this invention as shown in the drawings. Numeral 1 indicates a rotary cam block for producing patterns comprising a plurality of concentric circles divided on one side thereof and each section constitutes a different rugged cam track, for example, the cam tracks a, b, c, d and e. The rotary cam block 1 is mounted on a control shaft 2 which is rotated by the drive shaft 5 of the sewing machine through a worm 4 and a worm gear 3. A nut 2a clamps cam block 1 detachably against a shoulder 2b of shaft 7. A support shaft 7 extends perpendicular to the axis of rotation of cam block 1 and support a cam follower means 6 for sliding movement in axial direction of support shaft 7, and in radial direction with respect to cam block 1, and its cam tracks. A guide shaft means 12 extends parallel to support shaft 7 and supports a selector 9 for sliding movement thereon. Selector member 9 has an arm with a pair of forked portions slidable on shaft 7 and located on opposite sides of a hub portion of cam follower means 6. A handle 13 forms part of selector 9 so that the latter can be manually moved along shafts 7 and 12 to place cam follower 6 on selected cam tracks of cam block 1.

Selector 9b has a collar, best seen in FIG. 4, formed with a segment-shaped slot 9a into which a catch 11 projects under the action of a spring 14. Catch 11 is mounted for angular movement on selector 9 by means of pivot screwlla.

Guide shaft 12 has axially spaced grooves 16 into which catch 11 projects in successive positions of selector 9. The lateral faces of grooves 16 are frustoconical so that upon axial movement of selector 9, catch 11 is urged out of a groove 16 and assumes a position releasing the respective groove 16 while turning in slot 9a. When after further movement of selector 9, slot 9a is located opposite the next groove 16, spring 14 snaps catch 11 into the next groove, and it will be understood that cam follower 6 is located opposite a different cam track in each position of selector 9.

A rocking member 8 is mounted on support shaft 7 non-movable in axial direction and turnable on the same. Rocking member 8 carries a pin 80 which extends parallel to shaft 7 and passes through a slot in an arm of cam follower means 6. Consequently cam follower means 6 oscillates rocking member 8 in all position-s of selector 9.

Rocking member 8 has a forked arm receiving a pin 17 on another rocking member 10 which is turnable about the pivot screw 18 and has another pivot screw 20 to which a connecting rod 19 is turnably connected. Connecting rod 19 forms part of a linkage, not shown, which connects rocking member 19 with the needle bar so that oscillation of the cam follower 6 will result in transverse oscillation of the needle bar whereby a zigzag pattern is stitched.

Before selector member 13 is shifted, a knob, not shown, which is connected with connecting rod 19, is operated to effect movement of rod 19 to the left as viewed in FIG. 1 whereby members 10 and 8 are turned to a position in which cam follower means 6 is retracted from the cam tracks, and in this position, selector 9 is shifted by operation of handle 13, to place cam follower 6 opposite a selected cam track. Thereupon, the above mentioned knob, not shown, is turned back so that cam follower 6 engages the selected cam track.

Before the setting member 13 is shifted, a knob, now

shown, which is connected with the connecting rod 19,

is operated to effect movement of the connecting rod 19 to the left as viewed in FIG. 1, and turning of members '10 and 8 to a position in which cam follower 6 is retracted from the cam tracks, and in this position, selector member 13 is shifted to place cam follower 6 opposite a newly selected cam track, whereupon the above-mentioned knob, not shown, is turned back so that cam follower 6 engages the selected cam track. Since the rotary profiling member comprises a variety of rugged cam track surfaces, various kinds of zigzag patterns can be sewn. The rotary cam block is of small dimensions as are the rug ged cam tracks on its side, and it is therefore convenient for mounting in a machine. Furthermore, operation is reliable as the rotary cam block is mounted on the rotary control shaft 2 which is associated with the drive shaft of the machine and the cam follower 6 which contacts the selected rugged cam tracks transmits its mot-ion to the needle bar through a linkage comprising the parts 80, 8 1,

10, 19 and other conventional parts, now shown.

I claim:

1. In a Zigzag sewing machine, in combination, a drive shaft; a control shaft driven by said drive shaft; a cam block secured to said control shaft for rotation with the same about an axis, said cam block having a face perpendicular to said axis formed with a plurality of circular cam tracks concentric with said axis and having different cam track patterns; a support shaft perpendicular to said axis; a cam follower means mounted on said support shaft for reciprocating movement about the axis of said support shaft, and also for movement in axial direction of said support shaft and in radial direction of said cam block between a plurality of positions engaging different cam tracks of said cam block; a guide means parallel to said support shaft; a manually operated selector member mounted on said guide means movable along the same and along said support shaft and connected to said cam follower means for moving the same between said positions; and means for connecting said cam follower means with the needle bar of the sewing machine so that the needle bar is oscillated in zigzag stitch patterns corresponding to said cam track patterns.

2. In a zigzag sewing machine, in combination, a drive shaft; a control shaft driven by said drive shaft, said control shaft having a reduced at least partly threaded portion bounded by a shoulder; an integral cam block seated on said control shaft portion; threaded means threadedly engaging said control shaft portion to clamp said cam block detachably against said shoulder so that said cam block is secured to said control shaft for rotation with Patented Nov. 6, 1962 the same about an axis, said cam block having a face perpendicular to said axis formed with a plurality of circular cam tracks concentric with said axis surrounding said shoulder and having different cam track portions; a support shaft perpendicular to said axis; a cam follower means mounted on said support shaft for reciprocating turning movement about the axis of said support shaft, and also for movement in axial direction of said support shaft and in radial direction of said cam block between a plurality of positions engaging different cam tracks of said cam block; a manually operated selector member movable along said support shaft connected to said cam follower means for moving the same between said positions; and means for connecting said cam follower means with the needle bar of the sewing machine so that the needle bar is oscillated in zigzag stitch patterns corresponding to said cam track patterns.

3. In a zigzag sewing machine, in combination, a drive shaft; a control shaft driven by said drive shaft; a cam block secured to said control shaft for rotation with the same about an axis, said cam block having a face perpendicular to said axis formed with a plurality of circular cam tracks concentric with said axis and having different cam track patterns; a support shaft perpendicular to said axis; a cam follower means mounted on said support shaft for reciprocating turning movement about the axis of said support shaft, and also for movement in axial direction of said support shaft and in radial direction of said cam block between a plurality of positions engaging different cam tracks of said cam block; a guide shaft means parallel to said support shaft; a manually operated selector member mounted on said guide shaft means movable along the same and having a portion slidable on said support shaft and connected to said cam follower means for moving the same between said positions; a rocking arm member mounted on said support shaft non-movable in axial direction and turnable on the same; means for connecting said cam follower means with said rocking arm member for turning movement therewith and including a forked part of said cam follower means, and an elongated pin slidably disposed in said forked part and secured to said arm member; and means for connecting said rocking member with the needle bar of the sewing machine so that the needle bar is oscillated in zigzag stitch patterns corresponding to said cam track patterns.

4. In a zigzag sewing machine, in combination, a drive shaft; a control shaft; worm gear means connecting said shafts so that said control shaft is driven by said drive shaft, said control shaft having a reduced at least partly threaded portion bounded by a shoulder; an integral cam block seated on said control shaft portion; threaded means threadedly engaging said control shaft portion to clamp said cam block detachably against said shoulder so that said cam block is secured to said control shaft for rotation with the same about an axis, said cam block having a face perpendicular to said axis formed'with a plurality of circular cam tracks concentric with said axis surrounding said shoulder and having diiferent cam track patterns; a support shaft perpendicular to said axis; a cam follower means mounted on said support shaft for reciprocating turning movement about the axis of said support shaft, and also for movement in axial direction of said support shaft and in radial direction of said cam block between a plurality of positions engaging different cam tracks of said cam block; a guide shaft means parallel to said support shaft; a manually operated selector member mounted on said guide shaft means movable along the same and along said support shaft and connected to said cam follower means for moving the same between said positions; a catch on said selector member cooperating with said guide shaft means; a rocking arm member mounted on said support shaft non-movable in axial direction and turnable on the same; means for connecting said cam follower means with said rocking arm member for turning movement therewith and including a forked part of said cam follower means, and an elongated pin slidably disposed in said forked part and secured to said arm member; and means for connecting said rocking member with the needle bar of the sewing machine and including another rocking member, a connecting pin on said other rocking member, a forked part on said rocking arm member turnably receiving said connecting pin, and a rod articulated to said other rocking member for connecting the same to the needle bar so that the needle bar is oscillated in zigzag stitch patterns corresponding to said cam track patterns.

References Cited in the file of this patent UNITED STATES PATENTS 2,005,070 Bitzer June 18, 1935 2,701,108 Muschamp Feb. 1, 1955 2,743,622 Haupt May 1, 1956 2,833,233 DAmico May 6, 1958 2,900,937 Gegauf Aug. 25, 1959 2,906,219 Vigorelli Sept. 29, 1959 2,969,756 Eriksson Jan. 31, 1961 3,000,333 Moro Sept. 19, 1961 FOREIGN PATENTS 300,900 Switzerland Nov. 1, 1954 525,946 Italy May 12, 1955 552,428 Italy Dec. 3, 1956 1,143,023 France Apr. 8, 1957 783,358 Great Britain Sept. 25, 1957 

